1. Field of the Invention
The present invention relates generally to a semiconductor processing tool and, more specifically, to a thermal processing tool with a UV radiation source.
2. Description of the Related Art
Rapid Thermal Processing, commonly referred to as ‘RTP’, subjects a substrate to a very brief, intense burst of heat that can go from room temperature to about 1000° C. in seconds. RTP technology is used to change the characteristics of a deposited film or crystal lattice. RTP generally includes processes such as annealing, silicidation and oxidation of a substrate surface.
Generally, an RTP chamber includes a radiant heat source or lamp, a chamber body, and a substrate support ring. The lamp is typically mounted on a top surface of the chamber body so that the energy generated by the lamp radiates upon the substrate supported by the substrate support ring with in the chamber body. A quartz window is typically disposed in the top surface of the chamber body to facilitate the transfer of energy from the lamp to the substrate. An external motor is usually used to rotate the support ring and the substrate to compensate for variations in the radiation energy generated by the lamp that could heat the substrate non-uniformly. Typically, a rapid thermal process is performed at a reduced pressure to get better uniformity.
Thermal oxidation is commonly used to grow very thin layer of oxide used as gate oxide. An oxidation process performed in a state of the art RTP chamber usually include raising the temperature in the RTP chamber high enough to break oxygen or other species used to form an oxide layer and to allow enough diffusion of oxygen or other species occur on the substrate surface. The temperature needed to break oxygen or other species is usually higher than the temperature needed to induce enough diffusion. The higher temperature required for breaking oxygen or other species increases thermal exposure, promote unwanted diffusion inside other structures.
Therefore, there is a need for an apparatus and method for performing oxidation or other rapid thermal processes without the requirement of increased chamber temperature.